Congresso Brasileiro de Microbiologia 2023

Congresso Brasileiro de Microbiologia 2023

Resumo: 1225-1

1225-1

ANTIFUNGAL ACTIVITY OF Trichoderma afroharzianum FROM SALTA (ARGENTINA) AGAINST SOILBORNE PHYTOPATHOGENS

Autores:

Gabriel Caliuolo (UNSA SRMRF - Sede Regional Sur Metan, Universidad Nacional de Salta) ; Arnaldo Córdoba (UNSA SRMRF - Sede Regional Sur Metan, Universidad Nacional de Salta) ; Lorena Berruezo (EEA INTA - Estación Experimental Agropecuaria INTA Salta) ; Guadalupe Mercado Cárdenas (EEA INTA - Estación Experimental Agropecuaria INTA Salta, UNSA SRMRF - Sede Regional Sur Metan, Universidad Nacional de Salta) ; Eleonora Harries (EEA INTA - Estación Experimental Agropecuaria INTA Salta, CONICET - Consejo Nacional de Investigaciones Científicas y Técnicas, UNSA SRMRF - Sede Regional Sur Metan, Universidad Nacional de Salta)

Resumo:

Root diseases caused by soilborne fungal pathogens produce significative losses in tobacco yields. Its management is difficult because these phytopathogens forms resistance structures and lives by several years in soils infested. Biological control is an interesting approach to control fungal phytopathogens. The isolation and characterization of native Trichoderma spp. strains from Salta, Argentina, has been explored. In this study, were evaluated the inhibition of growth of seven phytopathogens with diffusible metabolites produced by Trichoderma afroharzianum. The cell-free culture filtrate of two T. afroharzianum strains (Th15, Th51) was prepared in Potato Saccharose Broth and incubated at 20 ± 4°C on agitation (140 rpm). Cell free supernatants were collected after 3 days of incubation by filtration through filter paper and centrifuged at 4000 rpm, 5 min. The growth inhibitory effects of diffusible metabolites from culture filtrates were analysed using plates of Potato Dextrose Agar (PDA) amended with 25% (v/v) cell free filtrate. Radial growth inhibitions against Fusarium oxysporum (Fo12, Fo13), Rhizoctonia solani (Rs56), Macrophomina phaseolina (Mp1T), Sclerotinia sclerotiorum (Ss1P), Phytophthora spp. (Phy1, Phy2) were tested. Percentages of radial growth inhibition (%I) for each pathogen were calculated relative to control. All the test phytopathogens analysed were significantly inhibited by diffusible metabolites produced by T. afroharzianum strains. The maximum inhibition of F. oxysporum was caused by diffusible metabolites of Th15, registered for Fo12 (79%I) and Fo13 (80%I). Also, diffusible metabolites of Th15 showed the highest inhibitory effect against Ss1P (81%), Mp1T (86%) and Phy2 (74%I). Meanwhile, diffusible metabolites of Th51 were more effective for Phy1 (82%I) and Rs56 (70%I). These results revealed that T. afroharzianum (Th15 and Th51) produced metabolites with antifungal action against different soilborne phytopathogens.

Palavras-chave:

ANTIFUNGAL, BIOCONTROL, METABOLITES, SOILBORNE PATHOGENS, TRICHODERMA

Agência de fomento:

PRESTAMO BID PICT2020, CIUNSA N° 2725, INTA PE I073